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I'm trying to figure out why my instrument cluster goes dead intermittently on start up, I've pulled the cluster and gone over the PC board with a 10x magnifier looking for cold solder joints and burnt traces and components, none found. I was wondering if it's possibly caused by an intermittent ignition switch since this provides the power to the cluster.
Any help would be appreciated.
 

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Sorry, the current chaos keeps me away, so apologies for the slow reply.

Can you give a bit of clarity to "goes dead intermittently on startup" All gauges go to 0, the lights go off, the back lighting dies? Important to know, as various pins on the ignition switch feed different things, and if one doesn't die and the other does, we can eliminate the switch (Also have not hard of this failure before.)

The back lighting is fed off the Tail fuse, 10A, which is pulled in by the TAIL relay, energized off the 50A Junction box fuse. This is not controlled by the ignition switch, but is always on. This controls your fog lamp sw, Auto LSD sw, DAC Sw, and diff lock sw (if you have these options), stuff on the steering wheel, Some of these are also affected by the dimmer switch, so it could be playing a role too. Your AC control panel lights, shift lever lights on the console, radio, hazard sw and the speedo itself are all lit by the same supply. So any of those being intermittent could be a problem. But most stuff dims during the starting routine.

The gauges are fed as part of the speedo (combination meter in manual talk) , off three separate sources. IG1 (10A) IG1 pin at Ign, and Gauge (7.5A) IG2 pin at Ign. IG2 pin also feeds the ignition coils. Third source is ECUB, a 7.5a fuse.

The various idiot lights on the dash are fed off the 7.5a gauge fuse

The IG1 seems to power up the various control pieces, like speed control to the combo meter.
 
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